CN112946520B

CN112946520B - Capacitive short circuit detection circuit, display device and capacitive short circuit detection method

Info

Publication number: CN112946520B
Application number: CN202110154926.6A
Authority: CN
Inventors: 杨阳; 孔祥梓; 吕博嘉; 黄高军
Original assignee: Xiamen Tianma Microelectronics Co Ltd
Current assignee: Xiamen Tianma Microelectronics Co Ltd
Priority date: 2021-02-04
Filing date: 2021-02-04
Publication date: 2023-06-23
Anticipated expiration: 2041-02-04
Also published as: CN112946520A

Abstract

The application discloses a short circuit detection circuit, display device and short circuit detection method of electric capacity, short circuit detection circuit of electric capacity includes: m capacitance short circuit detection units, an operation unit and an alarm unit; the detection end of each capacitor short circuit detection unit is connected with a non-grounding end of a capacitor on the flexible circuit board, and each capacitor short circuit detection unit is used for detecting whether the connected capacitor is short-circuited or not and outputting a detection result representing whether the capacitor is short-circuited or not to the operation unit; the output end of the operation unit is connected with the input end of the alarm unit, and the operation unit is used for performing AND operation on the detection results output by the capacitor short circuit detection units to obtain target signals and outputting the target signals to the alarm unit; the alarm unit is used for outputting an alarm signal when the received target signal is a preset signal. The capacitive short-circuit detection circuit disclosed by the application can detect whether a short-circuited capacitor exists on the flexible circuit board.

Description

Capacitive short circuit detection circuit, display device and capacitive short circuit detection method

Technical Field

The application belongs to the technical field of display, and particularly relates to a capacitive short circuit detection circuit, a display device and a capacitive short circuit detection method.

Background

The flexible circuit board (Flexible Printed Circuit, FPC) is a printed circuit board made of flexible insulating base materials, has the characteristics of high bending degree, high wiring density, thin thickness, small mass and the like, and is widely applied to electronic products.

However, during transportation of the FPC and during assembly of the FPC, the FPC is inevitably subjected to extrusion, electrostatic Discharge (ESD), overheat, overvoltage, and the like, resulting in a short circuit of the capacitor in the FPC. If the display device is produced using the FPC, an abnormality may occur in the produced display device.

Disclosure of Invention

The embodiment of the application provides a capacitor short circuit detection circuit, a display device and a capacitor short circuit detection method, which can solve the technical problem that whether a capacitor in an FPC is short-circuited can not be detected.

In one aspect, an embodiment of the present application provides a capacitive short-circuit detection circuit, including: m capacitance short circuit detection units, an operation unit and an alarm unit;

the detection end of each capacitor short circuit detection unit is connected with a non-grounding end of a capacitor on the flexible circuit board, the output end of each capacitor short circuit detection unit is connected to the input end of the operation unit, each capacitor short circuit detection unit is used for detecting whether the connected capacitor is short-circuited or not, and outputting a detection result representing whether the capacitor is short-circuited or not to the operation unit, and M is a positive integer;

the output end of the operation unit is connected with the input end of the alarm unit, and the operation unit is used for performing AND operation on the detection results output by the capacitance short circuit detection units to obtain target signals, and outputting the target signals to the alarm unit;

the alarm unit is used for outputting an alarm signal when the target signal is a preset signal, wherein the preset signal is a signal representing a capacitor with a short circuit.

In one or more embodiments of the present application, the M capacitive short circuit detection units and the arithmetic unit are disposed on a test board.

In one or more embodiments of the present application, the detection end of each of the capacitive short circuit detection units is electrically connected to a non-grounded end of the capacitor on the flexible circuit board through a test point on the flexible circuit board.

In one or more embodiments of the present application, the detection end of each of the capacitive short circuit detection units is electrically connected to a non-grounded end of the capacitor on the flexible circuit board by means of a probe or by means of a dummy voltage.

In one or more embodiments of the present application, the flexible circuit board is a flexible circuit board on a display device, and the M capacitance short-circuit detection units and the operation unit are disposed on a display driving chip of the display device.

In one or more embodiments of the present application, the detection end of each of the capacitive short circuit detection units is electrically connected to a non-grounded end of the capacitor on the flexible circuit board by means of a patch.

In one or more embodiments of the present application, the flexible circuit board is a flexible circuit board on a display device, and the M capacitance short-circuit detection units and the operation unit are disposed on a display panel of the display device.

In one or more embodiments of the present application, the alarm unit is disposed on a test board.

In one or more embodiments of the present application, the flexible circuit board is a flexible circuit board on a display device, and the alarm unit is disposed on a display panel of the display device.

In one or more embodiments of the present application, the alarm unit includes at least one of a display unit and a sound emitting unit.

In one or more embodiments of the present application, the capacitive short circuit detection unit includes:

the first switch subunit is used for charging the capacitor connected with the first switch subunit when the first switch subunit is in a closed state, and the second switch subunit is used for discharging the capacitor connected with the first switch subunit when the first switch subunit is in a closed state;

the first input end of the comparison subunit is connected to the second end of the first switch subunit, the second input end of the comparison subunit is connected to the reference signal end, the output end of the comparison subunit is connected to the input end of the alarm unit, and the comparison subunit is used for comparing the signal of the second end of the first switch subunit with the reference signal of the reference signal end and outputting the detection result according to the comparison result.

In one or more embodiments of the present application, the comparing subunit includes a comparator chip or a circuit composed of logic circuits.

In one or more embodiments of the present application, the capacitive short circuit detection circuit further includes:

and the grounding end is connected with the other non-grounding end of the capacitor, both ends of which are not grounded, on the flexible circuit board.

On the other hand, the embodiment of the application provides a display device, which comprises the capacitor short circuit detection circuit of any one of the above.

In still another aspect, an embodiment of the present application provides a capacitive short-circuit detection method, where the capacitive short-circuit detection method performs capacitive short-circuit detection by using the capacitive short-circuit detection circuit of any one of the foregoing, and the method includes:

the following steps are executed for each of the capacitive short circuit detection units: detecting whether the capacitor on the flexible circuit board is short-circuited or not through the capacitor short-circuit detection unit, and outputting a detection result representing whether the capacitor is short-circuited or not to the operation unit;

performing AND operation on the detection results output by the capacitance short circuit detection units through the operation unit to obtain target signals, and outputting the target signals to the alarm unit;

and outputting an alarm signal when the target signal is a preset signal, wherein the preset signal is a signal representing a capacitor with a short circuit.

In one or more embodiments of the present application, the outputting, to the arithmetic unit, a detection result indicating whether the capacitor is shorted, includes:

outputting a detection result of a low-level signal to the operation unit when the capacitance short circuit detection unit detects the capacitance short circuit;

and outputting a detection result of the high-level signal to the operation unit when the capacitor short circuit detection unit detects that the capacitor is not short-circuited.

According to the capacitive short-circuit detection circuit, the display device and the capacitive short-circuit detection method, the capacitive short-circuit detection circuit comprises M capacitive short-circuit detection units, an operation unit and an alarm unit, wherein the detection end of each capacitive short-circuit detection unit is connected with a non-grounding end of a capacitor on a flexible circuit board, so that each capacitive short-circuit detection unit can carry out short-circuit detection on the capacitor on the FPC and output detection results to the operation unit. And then, the operation unit performs AND operation according to the detection results output by the capacitance short circuit detection units to obtain a target signal, and outputs the target signal to the alarm unit. Under the condition that the received target signal is a preset signal, the alarm unit indicates that a short-circuit capacitor exists in the FPC, and then outputs an alarm signal, so that workers are prompted that the FPC is abnormal, the workers screen out the flexible circuit board, abnormal display devices are prevented from being produced by using the FPC, and the quality of the produced display devices is guaranteed.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of one embodiment of a capacitive short-circuit detection circuit provided in the present application.

Fig. 2 is a schematic structural diagram of another embodiment of a capacitive short-circuit detection circuit provided in the present application.

Fig. 3 is a schematic diagram of an embodiment of an and circuit provided in the present application.

Fig. 4 is a schematic diagram of another embodiment of an and circuit provided in the present application.

Fig. 5 is a schematic structural diagram of an embodiment of a capacitive short-circuit detection circuit electrically connected to a flexible circuit board.

Fig. 6 is a schematic structural diagram of another embodiment of the electrical connection between the capacitive short-circuit detection circuit and the flexible circuit board.

Fig. 7 is a schematic structural diagram of another embodiment of the electrical connection between the capacitive short-circuit detection circuit and the flexible circuit board.

Fig. 8 is a schematic structural diagram of still another embodiment of the electrical connection between the capacitive short circuit detection circuit and the flexible circuit board provided in the present application.

Fig. 9 is a schematic structural diagram of still another embodiment of the electrical connection between the capacitive short-circuit detection circuit and the flexible circuit board.

Fig. 10 is a schematic structural diagram of still another embodiment of the electrical connection between the capacitive short-circuit detection circuit and the flexible circuit board.

Fig. 11 is a schematic structural diagram of an embodiment of a capacitive short-circuit detection unit provided in the present application.

Fig. 12 is a schematic structural diagram of still another embodiment of the electrical connection between the capacitive short circuit detection circuit and the flexible circuit board provided in the present application.

Fig. 13 is a schematic flow chart diagram of an embodiment of a capacitive short circuit detection method provided in the present application.

Detailed Description

Features and exemplary embodiments of various aspects of the present application are described in detail below to make the objects, technical solutions and advantages of the present application more apparent, and to further describe the present application in conjunction with the accompanying drawings and the detailed embodiments. It should be understood that the specific embodiments described herein are intended to be illustrative of the application and are not intended to be limiting. It will be apparent to one skilled in the art that the present application may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present application by showing examples of the present application.

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises an element.

At present, flexible circuit boards are widely used in electronic products, for example, flexible circuit boards can be used in mobile phones and wearable devices. In order to make the volume of electronic equipment smaller, the capacitor type package on the flexible circuit board is smaller, and accordingly, the capacitor performance and reliability on the flexible circuit board are reduced, so that the capacitor is easy to fail.

When the flexible Circuit board is produced, the electrical performance and the electrical connection of the flexible Circuit board can be tested by means of functional Test (Functional Circuit Test, FCT) or In-line Test (ICT) and the like so as to check whether the flexible Circuit board produced by production has defects and whether components and devices are bad. In the two test modes, on-line single components and the open and short circuit conditions of each circuit network are mainly checked, and the method has the characteristics of simplicity in operation, rapidness, accuracy in fault positioning and the like. Fly needle ICT usually performs static test, and has the advantages of no need of manufacturing clamp and short program development time.

After testing of the flexible circuit board is completed, the flexible circuit board needs to be transported to a device manufacturer for assembly into an electronic device.

However, during transportation of the flexible wiring board and during assembly of the flexible wiring board, the flexible wiring board is inevitably subjected to extrusion, electrostatic Discharge (ESD), overheat, overvoltage, and the like, resulting in a short circuit of the capacitor in the flexible wiring board. However, for this situation, there is currently no effective solution to detect whether a short circuit has occurred in the capacitance of the flexible circuit board. If the display device is produced using a flexible wiring board having a failure capacitance, an abnormality may occur in the produced display device.

In order to solve the technical problem that whether the capacitor in the flexible circuit board is short-circuited can not be detected, the application provides a capacitor short-circuit detection circuit. The capacitance short circuit detection circuit comprises M capacitance short circuit detection units, an operation unit and an alarm unit, wherein M is a positive integer.

Each capacitor short circuit detection unit is connected with a capacitor on the flexible circuit board and is used for detecting whether the capacitor connected with the capacitor short circuit detection unit is short-circuited or not and outputting a detection result to the operation unit.

And the operation unit performs AND operation on the detection results output by the capacitance short circuit detection units to obtain a target signal, wherein the target signal reflects whether a short circuit capacitor exists in the flexible circuit board. Then, the arithmetic unit outputs the target signal to the alarm unit.

And the alarm unit outputs an alarm signal under the condition that the received target signal is a preset signal, wherein the alarm signal is used for prompting a user that a short-circuit capacitor exists on the flexible circuit board. Under the condition that the tester receives the alarm signal, the flexible circuit board can be intercepted, and the flexible circuit board is prevented from being used for producing the display device, so that the quality of the produced display device is improved.

The capacitive short circuit detection circuit provided by the present application is described below with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of an embodiment of a capacitive short-circuit detection circuit 100 provided herein. As shown in fig. 1, the capacitive short-circuit detection circuit 100 includes M capacitive short-circuit detection units 102, an operation unit 104, and an alarm unit 106.

The detection end of each capacitor short circuit detection unit 102 is connected to a non-grounded end of a capacitor on the flexible circuit board, the output end of each capacitor short circuit detection unit 102 is connected to the input end of the operation unit 104, and each capacitor short circuit detection unit 102 is used for detecting whether the connected capacitor is short-circuited or not and outputting a detection result representing whether the capacitor is short-circuited or not to the operation unit 104.

The output end of the operation unit 104 is connected to the input end of the alarm unit 106, and the operation unit 104 is configured to perform an and operation on the detection results output by the capacitance short circuit detection units 102, obtain a target signal, and output the target signal to the alarm unit 106.

The alarm unit 106 is configured to output an alarm signal when the received target signal is a predetermined signal, where the predetermined signal is a signal indicating that a capacitor having a short circuit exists.

In this embodiment of the present application, when the target signal received by the alarm unit 106 is a predetermined signal, it is indicated that a capacitor with a short circuit appears in the flexible circuit board, and an alarm signal is output. The alarm signal can prompt the staff that the short-circuit capacitor is arranged in the flexible circuit board, so that the staff screens the flexible circuit board, the abnormal display device is produced by the flexible circuit board with the short-circuit capacitor is avoided, and the quality of the produced display device is ensured.

In addition, one capacitance short circuit detection unit 102 may detect whether one capacitance is short-circuited. And there are M capacitive short-circuit detection units 102 in the capacitive short-circuit detection circuit 100, where M may be an integer greater than 1. In this case, the short-circuit detection can be performed simultaneously on M capacitors on the flexible circuit board by the capacitance short-circuit detection circuit 100, and the efficiency of the capacitance short-circuit detection can be improved. M may be equal to the amount of capacitance on the flexible circuit board. Thus, whether the short circuit occurs in each capacitor on the flexible circuit board can be detected at one time.

The capacitive short-circuit detection circuit 100 provided in the present application is described below with reference to fig. 2, and the operation unit 104 is taken as an and gate.

As shown in fig. 2, the output terminal of each of the capacitance short circuit detection units 102 is connected to the input terminal of the and gate, and when the capacitance short circuit detection unit 102 detects that the connected capacitance is short-circuited, the capacitance short circuit detection unit 102 outputs a low-level signal to the and gate. When the capacitance short circuit detection unit 102 detects that the connected capacitance is not short-circuited, the capacitance short circuit detection unit 102 outputs a high level signal to the and gate.

After receiving the signals Xi (i is any integer from 1 to M) output by the respective capacitance short-circuit detection units 102, the and gate performs an and operation on the signals Xi output by the respective capacitance short-circuit detection units 102, thereby obtaining target signals. That is, the target signal y=x1×x2× … xi× … XM output from the and gate.

If the signal Xi output by each capacitance short circuit detection unit 102 is a high level signal, that is, there is a capacitance on the flexible circuit board in which no short circuit occurs, the target signal output by the and gate is a high level signal. If the signal output by the at least one capacitance short circuit detection unit 102 is a low level signal, that is, if at least one capacitance is short-circuited, the target signal output by the and gate is a low level signal.

In the case where the target signal output from the and gate is a low level signal, the alarm unit 106 outputs an alarm signal to prompt the staff that there is a capacitor in the flexible circuit board where a short circuit occurs.

The schematic diagram of the and gate is described below.

Fig. 3 is a schematic diagram of one embodiment of an and circuit provided herein. In fig. 3, the and gate may be implemented using CMOS logic. Fig. 4 is a schematic diagram of another embodiment of an and circuit provided herein. In fig. 4, the and gate may be implemented using a diode.

The implementation principle of the and gate will be described below by taking the and gate of fig. 4 as an example.

As shown in fig. 4, vcc=5v, r1=3k9, and 3V and above are assumed to represent high level, and 0.7V and below are assumed to represent low level.

When a=b=0v, the diodes D1 and D2 are forward biased, and both the diodes D1 and D2 are turned on, and at this time, the potential of Y is 0.7V, and the output is low.

When one of a and B is at a high level and the other is at a low level, it is assumed that a=3v and b=0v. The analysis may be started from the diode D2, the diode D2 is turned on, and after the diode D2 is turned on, the voltage drop of the diode D2 is limited to 0.7V, so that the diode D1 is reverse biased and turned off because the right side is 0.7V and the left side is 3V, so that finally Y is 0.7V, that is, Y is a low level output.

At a=b=3v, both diodes D1 and D2 will be forward biased, with Y being limited to 3.7V, i.e., Y is a high output.

Based on the analysis described above, a truth table for the and gate can be derived as shown in table 1.

TABLE 1

Input A	Input B	Output Y
			0	0	0
0	1	0
			1	0	0
1	1	1

In one or more embodiments of the present application, as shown in fig. 5, M capacitance short detection units 102 and an arithmetic unit 104 are disposed on a test board 108. Wherein the test board 108 can be removably electrically connected to the flexible circuit board 200.

In the embodiment of the present application, the M capacitance short-circuit detection units 102 and the operation unit 104 are disposed on the test board 108, instead of disposing the capacitance short-circuit detection units 102 and the operation unit 104 on an existing module (such as the display panel 500) of the display device, and thus, there is no need to change the circuit structure of the existing module. The test board 108 is added on the basis of the existing scheme, so that the implementation of the capacitance detection scheme is facilitated.

As one example, the alarm unit 106 may be provided on a test plate.

As another example, the alarm unit 106 may not be provided on the test plate. Specifically, the alarm unit 106 may be disposed on the display panel 500 of the display device.

For example, the alarm unit 106 is an indicator light, which is disposed on the display panel 500, and the indicator light can be used to indicate whether the capacitor on the flexible circuit board 200 is shorted. In addition, the indicator light may be used to indicate whether the electronic device has received a new message. That is, the indicator light may have multiple functions.

In addition, the display function of the display panel 500 can be used for alarming, no additional device for alarming is needed, and the display function of the display panel 500 is fully utilized. Since the means for alerting is saved, not only some costs can be saved, but also space for the test board 108.

In one or more embodiments of the present application, the detection terminal of each capacitive short detection unit 102 is electrically connected to a non-grounded terminal of a capacitor on the flexible circuit board 200 through a test point on the flexible circuit board 200.

Specifically, as shown in fig. 6, when detecting whether a short circuit occurs in the capacitor on the flexible circuit board 200, a non-grounded end of the capacitor on the flexible circuit board 200 is electrically connected to a gold finger on the flexible circuit board 200, the gold finger is electrically connected to a test point TPi '(i is any integer from 1 to M) on the flexible circuit board 200, and the test point TPi' on the flexible circuit board 200 is electrically connected to the detection end TPi of the capacitor short circuit detection unit 102 in a one-to-one correspondence. Specifically, the test point TP1 'on the flexible circuit board 200 is electrically connected to the test end TP1 of the capacitive short circuit test unit 102, the test point TP2' on the flexible circuit board 200 is electrically connected to the test end TP2 of the capacitive short circuit test unit 102, and so on.

In this way, a non-ground terminal of the capacitor on the flexible circuit board 200 is electrically connected to the detection terminal of the capacitor short-circuit detection unit 102, so that the short-circuit detection is performed on the connected capacitor by the capacitor short-circuit detection unit 102.

In this embodiment of the present application, the connection mode between the capacitor on the flexible circuit board 200 and the capacitor short circuit detection unit 102 is relatively simple, and the arrangement mode of the capacitor on the flexible circuit board 200 does not need to be changed, so that the implementation of the capacitor detection scheme is facilitated.

In one or more embodiments of the present application, the detection end of each capacitive short circuit detection unit 102 is electrically connected to a non-grounded end of a capacitor on the flexible circuit board 200 by means of a probe. The probe is a test needle for testing, the surface of the probe is gold-plated, and the inside of the probe is provided with a high-performance spring with the average service life of 3-10 ten thousand times.

In one or more embodiments of the present application, the detection end of each capacitive short circuit detection unit 102 is electrically connected to a non-grounded end of the capacitor on the flexible circuit board 200 by way of a dummy voltage.

The detection end of each capacitor short circuit detection unit 102 is electrically connected with a non-grounding end of a capacitor on the flexible circuit board 200 by means of a probe or a dummy voltage, so that the test board 108 and the flexible circuit board 200 can be detachably connected. That is, after testing whether the capacitance on the flexible wiring board 200 is shorted using the test board 108, the connection between the test board 108 and the flexible wiring board 200 may be removed. In this way, when the flexible wiring board 200 is assembled to produce the display device, an increase in the volume of the display device due to the addition of the test board 108 is avoided.

Since some of the capacitors on the flexible circuit board 200 are not grounded at both ends, in order to ensure that one end of the capacitor is grounded when testing whether the capacitor is shorted, in one or more embodiments of the present application, the capacitor short detection circuit 100 may further include a ground terminal.

The ground terminal is connected to another ungrounded terminal of the capacitor on the flexible circuit board 200, which is ungrounded at both ends.

An embodiment of the present application is described below by way of fig. 7.

As shown in fig. 7, both ends of the capacitor C7 and the capacitor C8 on the flexible wiring board 200 are not grounded. Two ends of the capacitor C7 are connected to the test points TP7 'and TP8' on the flexible circuit board 200, respectively, while the test point TP7 'on the flexible circuit board 200 is connected to the test end TP7 of the capacitive short circuit detection unit 102 in the capacitive short circuit detection circuit 100, and the test point TP8' on the flexible circuit board 200 is connected to the ground end TP8 in the capacitive short circuit detection circuit 100. In this way, one end of the capacitor C7 is grounded, and the other end is connected to the detection end TP7 of the capacitor short detection unit 102.

The capacitor C8 is similar to the capacitor C7, two ends of the capacitor C8 are connected to the test points TP9 'and TP10' on the flexible circuit board 200, respectively, while the test point TP9 'on the flexible circuit board 200 is connected to the test end TP9 of the capacitive short circuit detection unit 102 in the capacitive short circuit detection circuit 100, and the test point TP10' on the flexible circuit board 200 is connected to the ground end TP10 in the capacitive short circuit detection circuit 100. In this way, one end of the capacitor C8 is grounded, and the other end is connected to the detection end TP9 of the capacitor short detection unit 102.

In this way, one ends of the capacitor C7 and the capacitor C8 can be grounded. After one ends of the capacitor C7 and the capacitor C8 are grounded, it is possible to detect whether the capacitor C7 and the capacitor C8 are shorted.

In this embodiment, the capacitive short-circuit detection circuit 100 includes a grounding terminal, so that one end of a capacitor with both ends not grounded on the flexible circuit board 200 is grounded, thereby implementing short-circuit detection on each capacitor on the flexible circuit board 200.

In one or more embodiments of the present application, the flexible circuit board 200 is a flexible circuit board 200 on a display device, and the m capacitance short-circuit detection units 102 and the operation unit 104 are disposed on a display driving chip 400 of the display device.

An embodiment of the present application is described below with reference to fig. 8.

As shown in fig. 8, a Chip On Flex (COF 300) 300 of the Display device is connected to a flexible circuit board 200 by a gold finger, a Display Driver IC (DDIC) 400 is provided On the COF300, and m capacitance short circuit detection units 102 and an arithmetic unit 104 are provided On the Display Driver Chip 400. The alarm unit 106 is disposed on the test board 108.

It should be noted that, the flexible circuit board 200 has a binding area formed by a plurality of golden conductive contacts arranged in order, and looks like a golden finger, so the flexible circuit board is called a golden finger in the industry. The golden finger is used for connecting the components.

In the embodiment of the present application, the M capacitive short circuit detection units 102 and the operation unit 104 are integrated on the display driving chip 400, and the capacitive short circuit detection units 102 and the operation unit 104 may be built up by logic devices. In this way, the volumes of the capacitive short circuit detection unit 102 and the operation unit 104 are smaller, and the space occupied by the capacitive short circuit detection unit 102 and the operation unit 104 is saved.

In addition, by integrating the M capacitance short-circuit detection units 102 and the operation unit 104 on the display driving chip 400, the M capacitance short-circuit detection units 102 and the operation unit 104 are included in the display device when the display device is assembled using the flexible wiring board 200. In this way, whether the capacitance on the flexible wiring board 200 is shorted or not can be detected in real time by the M capacitance short detection units 102 and the operation unit 104. For example, after the display device is assembled using the flexible wiring board 200, whether or not a short circuit occurs in the capacitance on the flexible wiring board 200 may be detected using the capacitance short circuit detection circuit 100. Alternatively, after the user uses the display device, if the display device fails, the capacitance short detection circuit 100 may be used to detect whether the capacitance on the flexible circuit board 200 is shorted, to assist in determining the cause of the failure of the display device.

In one or more embodiments of the present application, the detection end of each capacitive short circuit detection unit 102 is electrically connected to a non-grounded end of a capacitor on the flexible circuit board 200 by means of a patch.

In this way, an effective and reliable connection between the capacitance short-circuit detection unit 102 and the capacitance on the flexible wiring board 200 can be ensured.

In one or more embodiments of the present application, as shown in fig. 9 and 10, M capacitance short-circuit detection units 102 and arithmetic units 104 are disposed on a display panel 500 of a display device.

By providing the M capacitive short-circuit detection units 102 and the arithmetic unit 104 on the display panel 500, the M capacitive short-circuit detection units 102 and the arithmetic unit 104 are included in the display device when the display device is assembled using the flexible wiring board 200. In this way, whether the capacitance on the flexible wiring board 200 is shorted or not can be detected in real time by the M capacitance short detection units 102 and the operation unit 104. For example, after the display device is assembled using the flexible wiring board 200, whether or not a short circuit occurs in the capacitance on the flexible wiring board 200 may be detected using the capacitance short circuit detection circuit 100. Alternatively, after the user uses the display device, if the display device fails, the capacitance short detection circuit 100 may be used to detect whether the capacitance on the flexible circuit board 200 is shorted, to assist in determining the cause of the failure of the display device.

The difference between fig. 9 and 10 is that in fig. 9, the alarm unit 106 is provided on the test board 108, and in fig. 10, the alarm unit 106 is provided on the display panel 500.

In practice, the alarm unit 106 may be provided on the test board 108 or on the display panel 500 according to implementation requirements.

When the alarm unit 106 is disposed on the display panel 500, the display function of the display panel 500 may be used for alarm, and the display function of the display panel 500 is fully utilized without adding additional devices for alarm. Since the means for alerting is saved, not only some costs can be saved, but also space for the test board 108.

In one or more embodiments of the present application, the alarm unit 106 includes at least one of a display unit and a sound emitting unit.

Wherein the display unit may comprise a display or a light emitting diode.

If the display unit includes a display, an alarm signal may be output by emitting light from the display or a text message may be displayed on the display to prompt a worker that a short-circuited capacitor exists on the flexible wiring board 200, thereby realizing an alarm.

If the display unit comprises a light emitting diode, an alarm signal may be output by the light emitting diode.

The sound generating unit may include a buzzer or a voice announcer.

If the sound generating unit includes a buzzer, an alarm signal may be output by the buzzer generating a sound.

If the sounding unit includes a voice broadcasting device, voice information can be sent through the voice broadcasting device to prompt the staff that a short-circuit capacitor exists on the flexible circuit board 200, so that an alarm is realized.

In the embodiment of the present application, the alarm unit 106 includes a display unit and a sound generating unit, which are commonly used, so that implementation of the capacitive short circuit detection scheme is facilitated.

In one or more embodiments of the present application, as shown in fig. 11, the capacitive short circuit detection unit 102 includes: a first switching subunit CT, a second switching subunit S0, and a comparing subunit A0.

The first end of the first switch subunit CT is connected to the power supply VCC, the second end of the first switch subunit CT is connected to the first end of the second switch subunit S0 and a non-grounded end of the flexible circuit board 200 corresponding to the capacitor C0, the second end of the second switch subunit S0 is grounded, the first switch subunit CT is configured to charge the capacitor C0 connected to the first switch subunit CT when in the closed state, and the second switch subunit S0 is configured to discharge the capacitor connected to the first switch subunit CT when in the closed state.

The first input end of the comparing subunit A0 is connected to the second end of the first switch subunit CT, the second input end of the comparing subunit A0 is connected to the reference signal end VREF, the output end of the comparing subunit A0 is connected to the input end of the alarm unit 106, and the comparing subunit A0 is configured to compare the signal of the second end of the first switch subunit CT with the reference signal of the reference signal end, and output a detection result according to the comparison result.

When the flexible circuit board 200 is normally operated, the first and second switching subunits CT and S0 are turned on. When the flexible circuit board 200 does not work normally and the capacitance detection is required, the first switch subunit CT is turned off, the second switch subunit S0 is turned on, and the capacitor C0 connected to the first switch subunit CT is charged. When the voltage on the capacitor C0 (i.e., the voltage of the second terminal of the first switching subunit CT) is greater than the reference voltage of the reference signal terminal VREF, the comparing subunit A0 outputs a low-level signal. Thereby, it is achieved whether the capacitor C0 is short-circuited or not.

After detecting whether the capacitor C0 is shorted, the first switch subunit CT is turned on, and the second switch subunit S0 is turned off, so as to discharge the capacitor C0, thereby avoiding affecting the normal operation of the capacitor C0.

The power supply VCC may be connected to a power supply (PVDD) or the like, and the capacitor may be charged by the power supply VCC when detecting a short circuit of the capacitor.

Each of the capacitive short-circuit detection units 102 in the capacitive short-circuit detection circuit 100 may have the above-described circuit configuration.

In the embodiment of the application, the circuit structure of the capacitive short-circuit detection unit 102 is relatively simple, so that the cost of the capacitive short-circuit detection circuit 100 can be saved, and the capacitive short-circuit detection circuit 100 is prevented from occupying an excessive space.

Embodiments of the present application are described below with reference to the capacitive short detection circuit 100 being disposed on the test board 108.

As shown in fig. 12, the capacitive short-circuit detection circuit 100 includes 9 capacitive short-circuit detection units 102, and each capacitive short-circuit detection unit 102 has the circuit configuration shown in fig. 11.

When detecting whether a short circuit occurs in the capacitor on the flexible circuit board 200, a non-grounded end of the capacitor on the flexible circuit board 200 is electrically connected to the golden finger, the golden finger is electrically connected to the test point TPi '(i is any integer from 1 to M) on the flexible circuit board 200, and the test point TPi' on the flexible circuit board 200 is electrically connected to the detection end TPi of the capacitor short circuit detection unit 102 in a one-to-one correspondence. Specifically, the test point TP1 'on the flexible circuit board 200 is electrically connected to the test end TP1 of the capacitive short circuit test unit 102, the test point TP2' on the flexible circuit board 200 is electrically connected to the test end TP2 of the capacitive short circuit test unit 102, and so on.

Each of the capacitance short-circuit detection units 102 detects whether or not a short circuit occurs in the capacitance connected thereto, and outputs the detection result to the and gate (i.e., the operation unit 104). And gate and performs an and operation on the detection result output from each capacitance short-circuit detection unit 102 to obtain a target signal, and outputs the target signal to alarm unit 106.

In one or more embodiments of the present application, the comparison subunit includes a comparator chip or a circuit composed of logic circuits.

As an example, if M capacitive short-circuit detection units 102 and arithmetic unit 104 are provided on test board 108, the comparison subunit may use an existing comparator chip. Thus, the capacitive short-circuit detection circuit 100 can be manufactured relatively easily to perform capacitive short-circuit detection.

If the M capacitive short-circuit detection units 102 and the operation unit 104 are disposed on the display driving chip 400 or the display panel 500, the comparison subunit may be constructed by a logic circuit, so as to avoid the capacitive short-circuit detection circuit 100 from occupying an excessive space.

The present application provides a display device including the capacitive short-circuit detection circuit 100 of any one of the above embodiments. The display device has the same technical effects as the capacitive short-circuit detection circuit 100, and will not be described herein.

The application also provides a capacitance short-circuit detection method, which is used for capacitance short-circuit detection through the capacitance short-circuit detection circuit of any one embodiment.

Fig. 13 is a schematic flow chart diagram of an embodiment of a capacitive short circuit detection method provided in the present application. As shown in fig. 13, the capacitive short circuit detection method 1300 includes:

s1302, for each capacitive short circuit detection unit, the following steps are performed: detecting whether a capacitor on the flexible circuit board is short-circuited or not through a capacitor short-circuit detection unit, and outputting a detection result representing whether the capacitor is short-circuited or not to an operation unit;

s1304, performing AND operation on the detection results output by the capacitor short circuit detection units through the operation unit to obtain a target signal, and outputting the target signal to the alarm unit;

s1306, when the target signal received by the alarm unit is a predetermined signal, the alarm signal is output, and the predetermined signal is a signal indicating that a short circuit exists in the capacitor.

In this application embodiment, through alarm unit output alarm signal to suggestion staff flexible line way board has unusually, makes the staff screen out flexible line way board, avoids using this flexible line way board to produce unusual display device, guarantees the quality of the display device who produces.

In one or more embodiments of the present application, outputting a detection result indicating whether the capacitor is shorted to the operation unit may include:

outputting a detection result of the low-level signal to the operation unit when the capacitance short circuit detection unit detects the capacitance short circuit;

when the capacitor short circuit detection unit detects that the capacitor is not short-circuited, the detection result of the high-level signal is output to the operation unit.

Thus, the operation unit performs AND operation on the detection results output by the capacitance short circuit detection units so as to output a target signal which can represent whether the short circuit capacitance exists on the flexible circuit board.

It should be clear that the present application is not limited to the particular arrangements and processes described above and illustrated in the drawings. For the sake of brevity, a detailed description of known methods is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method processes of the present application are not limited to the specific steps described and illustrated, and those skilled in the art can make various changes, modifications, and additions, or change the order between steps, after appreciating the spirit of the present application.

It should also be noted that the exemplary embodiments mentioned in this application describe some methods based on a series of steps. However, the present application is not limited to the order of the above-described steps, that is, the steps may be performed in the order mentioned in the embodiments, may be different from the order in the embodiments, or several steps may be performed simultaneously.

In the foregoing, only the specific embodiments of the present application are described, and it will be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the systems, modules and units described above may refer to the corresponding processes in the foregoing method embodiments, which are not repeated herein. It should be understood that the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present application, which are intended to be included in the scope of the present application.

Claims

1. A capacitive short-circuit detection circuit, comprising: m capacitance short circuit detection units, an operation unit and an alarm unit;

the alarm unit is used for outputting an alarm signal under the condition that the received target signal is a preset signal, wherein the preset signal is a signal representing a capacitor with a short circuit;

the capacitive short circuit detection unit includes:

2. The capacitive short-circuit detection circuit according to claim 1, wherein the M capacitive short-circuit detection units and the arithmetic unit are provided on a test board.

3. The capacitive short circuit detection circuit of claim 2, wherein the detection terminal of each capacitive short circuit detection unit is electrically connected to a non-grounded terminal of a capacitor on the flexible circuit board through a test point on the flexible circuit board.

4. The capacitive short circuit detection circuit according to claim 2, wherein the detection terminal of each capacitive short circuit detection unit is electrically connected to a non-grounded terminal of a capacitor on the flexible circuit board by means of a probe or by means of a dummy voltage.

5. The capacitive short-circuit detection circuit according to claim 1, wherein the flexible circuit board is a flexible circuit board on a display device, and the M capacitive short-circuit detection units and the arithmetic unit are disposed on a display driving chip of the display device.

6. The capacitive short circuit detection circuit of claim 5, wherein the detection terminal of each capacitive short circuit detection unit is electrically connected to a non-grounded terminal of a capacitor on the flexible circuit board by means of a patch.

7. The capacitive short-circuit detection circuit according to claim 1, wherein the flexible circuit board is a flexible circuit board on a display device, and the M capacitive short-circuit detection units and the arithmetic unit are disposed on a display panel of the display device.

8. The capacitive short-circuit detection circuit according to any one of claims 1 to 7, characterized in that the alarm unit is provided on a test board.

9. The capacitive short-circuit detection circuit according to any one of claims 1 to 7, characterized in that the flexible wiring board is a flexible wiring board on a display device, and the alarm unit is provided on a display panel of the display device.

10. The capacitive short-circuit detection circuit according to any one of claims 1 to 7, wherein the alarm unit includes at least one of a display unit and a sound generation unit.

11. The capacitive short-circuit detection circuit of claim 1, wherein the comparison subunit comprises a comparator chip or a circuit comprised of logic circuits.

12. The capacitive short-circuit detection circuit according to any one of claims 1 to 7, characterized in that the capacitive short-circuit detection circuit further comprises:

13. A display device, comprising: a capacitive short-circuit detection circuit according to any one of claims 1 to 12.

14. A capacitive short-circuit detection method, characterized in that the method performs capacitive short-circuit detection by the capacitive short-circuit detection circuit according to any one of claims 1 to 12, the method comprising:

and outputting an alarm signal under the condition that the target signal received by the alarm unit is a preset signal, wherein the preset signal is a signal representing a capacitor with a short circuit.

15. The method according to claim 14, wherein outputting a detection result indicating whether the capacitor is shorted to the operation unit includes: